1. Field of the Invention
The invention relates to a safety system for high current applications, a plug connector system equipped with such a safety system and an electrical system equipped with such a plug connector system.
2. Description of Related Art
In motor vehicles with an electric-powered drivetrain, i.e., electric or hybrid vehicles, high levels of electric power need to be transmitted from an energy source (for example a battery unit) to a consumer (for example electric refrigerant compressors). In order to keep the losses which occur during transmission as low as possible, the electrical (high current) system comprising the battery unit and the electric drive motor is operated with a comparatively high voltage, which is in particular higher than 12 V, 24 V, or 48 V, at which the vehicle electrical system of conventional motor vehicles is operated.
In addition to this high current system, the known vehicles with electric-powered drivetrain also possess a conventional vehicle electrical system which—as in conventional motor vehicles—is based on an electrical voltage of 12 V, 24 V, or 48 V. On the one hand, this means that the same components can be used for the vehicle electrical systems of conventional vehicles and of vehicles with an electric-powered drivetrain, saving on development and manufacturing costs. On the other hand, maintenance and repair work can be carried out on the vehicle electrical system by “normal” workshops, since, because of the weak electrical voltage, even a mistake made during maintenance does not result in a hazard to the servicing personnel.
In contrast, due to the high voltage used, the high current system of electric or hybrid vehicles represents a considerable danger potential. In many cases, individual components or even whole units of the high current system therefore need to be designed so as to be inaccessible to servicing personnel. This is done, for example, in that the components or units of the high current system are built into housings which cannot be opened, or cannot be opened without being damaged. In the event of a defect in a component integrated into a housing, only the entire unit can therefore be replaced by the servicing personnel, which due to the electrical insulation of the housing can be done largely without any danger. However, it is clear that the replacement of functionally serviceable components which are integrated into a unit with a component which is no longer functionally serviceable involves considerable and in principle unnecessary costs.
As with virtually all electrical systems, circuit breakers are also integrated in the high current system of motor vehicles with electric-powered drivetrain which fail (“blow”) in the event of a temporary unacceptably high current level, permanently interrupting the flow of current. As a result, the other high-quality components of the high current system are protected against damage.
In the present high current systems of motor vehicles with an electric-powered drivetrain, high current circuit breakers are regularly combined in a unit together with a plurality of other electrical components, wherein the components are protected against contact with servicing personnel through a housing which cannot be opened (without being damaged). However, this leads to the problem that if the high current circuit breaker “blows”, which is its fundamental function, it is not possible simply to replace the high current circuit breaker; the entire unit has to be replaced. In many cases this leads to unacceptably high repair costs.